Provides the interface between the PowerBook Duo computer, and the Duo Dock.
It mounts directly to the Duo Dock's main logic board, and plugs into the
matching connector on the PowerBook Duo rear panel, giving the Duo Dock
direct access to the microprocessor's 32-bit address bus, 32-bit data bus,
and control signals. It also provides access to power, control, and status
signals in other parts of the computer, and allows the Duo Dock to provide
power to the PowerBook Duo.